Gunfire control



y 1944. 4 R. N. LESNICK 2,349,101

GUN FIRE CONTROL Filed April 7, 1941 3 Sheets-Sheet l 4 INVENTOR 20R7 /V. AE'I/V/C'K BY Q M r an,

ATT NEYS I6, 1944. R. N. LESNICK 2,349,101

' GUN FIRE CONTROL Filed April 7, 1941 3 Sheets-Sheet 2 7 INVENTOR 05597 /V. ZESW/Ck.

16, 1944. R. N. LESNICK 2,349,101

GUN FIRE CONTROL Filed April 7, 1941 3 Sheets-Sheet s Z2 !NVENITOR fiUBF/QT /V. LFf/V/CK Patented May 16, 1944 GUNFIRE CONTROL Robert N. Lesnick, Brooklyn, N. Y., assignor to Brewster Aeronautical Corporation, Long Island City, N. Y.

Application April 7, 1941, Serial No. 387,245

8 Claims.

This invention relate to improvements in armament for aircraft, and more particularly to improvements concerned with control of the firing operation of machine guns mounted upon aircraft or the like.

The invention contemplates an improved method and means for controlling a machine gun mounted upon an airplane or other armed vehicle having structural elements thereof projecting into the normal range of the gun fire, whereby the gun fire is automatically interrupted whenever the gun is trained upon the vehicle projecting elements to prevent damage to the latter.

One of the objects of the invention is to provide an improved means for the purpose described which is simple and rugged and positive in action. Another object of the invention is to provide a device of the character described which is adapted to positively restrict the gun firing operation, as required, without interfering with free movement of the gun throughout the entire available range of training adjustment thereof. Other objects and advantages of the invention will appear from the specification hereinafter.

In the drawings:

Fig. 1 is a fragmentary side elevation of an airplane having a flexibly mounted machine gun arranged to be fired generally toward the rear of the airplane; I

Fig, 2 is a. section taken substantially along line 11-11 of Fig. l; 1

Fig. 3 is a side elevation of the machine gun of Fig. 1, showing portions of th gun mounting and. gun fire interrupting mechanism of the invention;

Fig. 4 is a transverse elevation of a portion of the gun fire interrupter device of Fig. 3;

5 is a section'taken substantially along line V-V of Fig. 4, showing the machine gun in adjusted positions; and

Fig 6 is a fragmentary section taken substantially along line VI- VI of Fig. 3.

The drawings illustrate the invention in connection with a machine gun I!) which is mounted within. a cockpit enclosure H! of an airplane fuselage M. The airplane empennage vertical fin and rudder structures are indicated at It, and the horizontal tail surfaces are indicated at l8.

The gun H] is illustrated as being mounted at opposite sides thereof upon a pair of bearer tubes 20 by means of slide connections adjacent opposite ends of the bearer tubes in such manner that the gun I!) will be reciprocable longitudinal-- ly upon the bearer tubes for recoil shock absorbing purposes, in the presently customary manner. The bearer tubes 20 are pivotally mounted upon a gun mount trunnion yoke 22 by means of bolts 24 which engage opposite arm portions of th trunnion yoke 22 with corresponding brackets 26 extending rigidly upwardly from the bearer tubes 2!] at opposite sides of the gun. Thus, the gun and bearer tube unit 20-10 is pivotally mounted upon the trunnion yoke 22 for ro-' tation about a horizontal axis extendin transversely of the longitudinal axis of the gun It, so that the gun II] is free to be rocked about the axis 25 extending through the bolts 24-44 for elevational adjustments of the gun; while at all times the gun is free to reciprocate longitudinally relative to thebearer tubes 20 for recoil shock absorbing purposes.

' The trunnion yoke 22 extends upwardly and in longitudinal continuation of a gun mounting column 30 and the yoke 22 is mounted upon the column 30 by means of a rotation connection device 32 so as to be rotatable relative thereto about a vertical axis 33. Thus, the gun i0 is arranged to be free to be rotated about the axis 33 for traverse or azimuth adjustments of the gun in accordance with aiming requirements. The post 3!),is mounted to extend rigidly from a cradle shaft 34 which is supported by means of a pair of spaced stationary bearings 36 mounted upon corresponding stationary supporting elements 31 of th airplane structure, so that the shaft 34 is disposed with its longitudinal axis of rotation substantially parallel to the thrust axis of the airplane. Thus, the gun support column 30 is pivotable about an axis extending longitudinally of the airplane, and the gun I!) is thereby adapted to be swung from its solid line central position of Fig. 5 to either side thereof as illustrated by broken lines in such manner as to be adapted to fire around the vertical tail surface structure It of the airplane. Preferably, a counterweight arm 38 is arranged to extend rigidly from the shaft 34 in diametrically opposed relation with respect to the column 30 so as to counterbalance the weight of the gun It when ro tated to either side of its upright central position.

. To forestall gunnery damage to the tail structure of the airplane through inadvertence of the gunner while attempting to shoot toward the rear and as close as possible to the tail structure thereof, a. gun fire control device is provided in the form of a templet 40 which is stationarily fixed to a suitable fixed portion 42 of the airplane structure and is arranged to cooperby means of a ball and socket joint connection 7 device 58; the center of rotation of which coincides with the point 54. The tracer finger 56 carries at its opposite end a contact portion 59 which is round nosed and spring pressed into sliding contact with the templet surface 52. Intermediately of its ends the tracer finger 56 is pivotally suspended at opposite sides thereof 'by means of a bolt connection (it! to one end of a push-pull-torque link 62 which extends upward ly therefrom into yoked connection by means of bolts '64 with corresponding oppositely extending portions of the brackets 26. The bolt connections 24-64 are so relatively arranged that the distance between the axes of pivoting defined by the'connections 24 and 64 isequal tothe distance between the axes of the connections 58 and 50 of the tracer, and thus a parallelogram motion device is provided. The link 52 is so longitudinally dimensioned and the connections 64 are so verticallypositioned-that whenever-the gun is aimed in the region of the .intersection of the median plane of the empennagegroup and the axis of rotation the tracer contact .portion 59 will be disposed on the line of the axis of rotation 35 of the cradleshaft 34. Hence, if the gun I!) is maintained in sighting relation upon the said region of intersection while being swung about the axis 35 of the cradle shaft 34 the tracer tube 56 will simply rotate about the line of'the axis 3501 rotation of the-cradle shaft 34'and thus the contact portion .59 will simply rotate against the center of the templet 40. However, any displacement .of the line of the gun sighting away from the region of intersection .referred to will cause the-contact portion 59 vto be similarly displaced relative to .the center of the templet 4i].

The inner surfaceportion v52 .of the templet is illustrated as being formed of electrical conductive materialand is electrically connected to a conductor 66 forming aportion of the circuit which controls the .firing operation of the gun H). The contact portion 5.9 is .also formed vof electrical conductive material .and .iselectrically connectedto another conductor fil -which forms another portion of the gun fire control circuit, so that whenever the tracer portion 59 contacts a'conductive portion of the .templet surface 52 the electrical circuit .to the .gun trigger control solenoid is.closed,-providing the gunners control device is .in .firing .condition. .As illustrated in Fig. 14, the templet surface 52 is provided with a mask of electrically insulating substance as at 68, and the .mask 68 is so shaped as .to resemble generally the silhouette of the airplane empennage structure as viewed from the gunners cockpit. Thus, whenever the tracer portion 59 rides over the mask 63 theelectrical circuit to the gun control solenoid is automatically broken, and consequently whenever the gun ID is aimed at the tail structure of the airplane thegun is. automatically prevented from firing even though the gunner may inadvertently have the gun fire control switchin operative position.

It will be understood that the mask 68 will be so formed and proportioned as to provide any desired factor of safety with respect to clearances between the line of gun fire and the airplane tail structure, and that the mask 68 will include vertically and laterally projecting portions corresponding to the silhouette of the empennage structural elements of the airplane as viewed from directly behind the gun from any position thereof which is made possible by the flexibl mounting arrangement mechanism upon which the gun is mounted. It will also be understood that the electrically conductive characteristics of the mask 68 and the remaining portion of the templet surface 52 may be reversed, if "desired, and that any other suitable form of tracer actionresponsive control mechanism may be employed inzlieu of the electrical circuit referred to, and that the tracer device will in any event be arranged to be operative to interrupt the gun firing operation whenever the gun is sighted toward the airplane empennage or wing or other projecting structure to be protected.

It is also contemplated that in lieu of the single gun mount as illustrated and described hereinabove in connection with the gun fire control device of the invention, any desired form of plural gun unit .may .be employed in connection with the invention. For example, a twin gun unit comprising a pair of parallel guns may be mounted .upon the column 30 to be carried thereby as in the manner of the single gun I!) of the drawings, .and in such case .a pair of corresponding tracer elements similar to the tracer device 5659 will be suitably mounted upon corresponding swivel connection devices so as to extend in substantially parallel relation and to cooperate with the templet 49 toindividually control the fire of the corresponding guns, as in the manner previously described hereinabove.

.IAlthOugh only one form of the invention has been shown and described .in detail, it will be apparent to those skilled in .the art that the in vention is not so'limited but that various changes may be made therein without departing from the spirit of the invention or the scope of the appended claims.

What is claimed is:

1. An aircraft, a gun adjustably mounted thereon for aiming purposes, said aircraft having a positionally fixed structure facing said gun under certain conditions of gun aim adjustment, said gun'being-mounted upon a shaft extending substantially toward said fixed structure, said shaft being rotatable about its longitudinal axis and said gun vbeingpivotally mounted relative to said shaft about an axisintersecting said shaft longitudinal axis andaboutanother axisdisposed transversely of said second mentioned axis, a tracer finger swivelly connected atone end to an end portion of said shaft and extending therefrom toward .said fixed structure, a templet fixed upon said aircraft and having an inner surface ,portion of spheric-alform engaging the free end .of said finger .in abutting relation and centered upon the position of intersection of said shaft longitudinal axis and said second mentioned axis, link means connecting at one of its ends with said gun at .a positionspaced .from the axes of said pivotal mountings and connecting at the other .of its ends with said finger at a position .spaced.from said swivel connection so as to cause said finger to move relative to said templet in accord with movements of said sun relative to ture'portion as viewed from the position of saidgunand adapted to register with said finger to-- 'sh'aftto extend therefrom in a transverse direction and to be rotatable about an axis substantially intersecting the longitudinal axis of rotation of said shaft, a gun mounted upon said gun mount post so as to be pivotable relative thereto about 'an' axis extending in a direction transverse to'the direction of the axis of rotation of said gun mount post relative to said shaft, a tracer finger swivelly connected at one end to an end portion of said shaft and extending therefrom toward said fixed structure portion, a templet fixed upon said aircraft and having an inner surface portion of spherical formengaging the free end of said finger in abutting relation and con; te'red upon theposition ofj'intersection'of said shaftlongitudinal axis and said second men' tioned' axis, link means connecting at one of its ends with said gun at a position spaced from the axes of said pivotal mountings and connecting at the other of its ends with said finger at a position spaced from said swivel connection so as to cause said finger to move relative to said templet in accord with movements of said gun relative to the direction of said fixed structure portion, said templet being provided with complementing electrically conductive and electrically-insulative surface portions contoured to correspond to the outline of said fixed structure portion as'viewed from the position of said gun and adapted to register with said finger to provide in cooperation therewith electrical circuit make and break means arranged to control the firing of said gun.

3. An aircraft having a positionally fixed structure portion, a shaft mounted upon said aircraft to extend substantially toward said fixed structure portion and to be rotatable about its longitudinal axis, a gun mount post carried by said shaft to extend therefrom in a transverse direction and to be rotatable about an axis substantially intersecting the longitudinal axis of rotation of said shaft, a gun mounted upon said gun mount post so as to be pivotable relative thereto about an axis extending in a direction transverse to the direction of the axis of rotation of said gun mount post relative to said shaft, a tracer finger swivelly connected at one end to an end portion of said shaft and extending therefrom toward said fixed structure portion, a templet fixed to engage the free end of said finger in abutting relation, link means connecting at one end with said gun at a position spaced from the axes of said gun and gun mount post pivotal mountings and connecting at the other end with said finger at a position spaced from said swivel connection so as to cause said finger to move relative to said templet in accord with movements of said gun relative to the direction of said fixed structure portion, said templet being provided with complementing electrically conductive and electrically insulatlve surface portions contoured to correspond to the outline of said fixed strucprovide'in cooperation therewith electrical circuit'make and break means arranged to control the'firing of said gun. i

4'; An aircraft having a positionally fixed struc'-- ture portion, a shaft mounted upon said aircraft to extend substantially toward said fixed structure portion and to be rotatable about its longi-- tudinal axis, a gun-mount post carried by saidshaft to extendtherefromin a transverse direction and to be' rotatable about an axis substan tiallyintersecting the longitudinal axis of rotation of said shaft, a gun mounted upon said gun mount post so as to be pivotable relative thereto:

about an axis extending in a direction transverse to the direction of the axis of rotation of said gun mount post relative to said shaft, a tracer finger swivelly connected at one end to an end portion of said shaft and extending therefrom towards'aidfixed structure portion, a templet fixed to engage the free end of said finger in abutting relation, link means connecting at one end with said gun at a position spaced from the axes of said gun and gun mount post pivotal mountings and'connecting at the other end with said finger at a position spaced from said swivel connection so as to cause said finger to move relative to saidtemplet in accord with movements of said gun relative to the direction of said fixed structure portion, said templet being provided with tracer finger contact surface portions contoured to correspond to the outline of said fixed structure portion as viewed from the position of said gun and adapted to register with said finger to provide in cooperation therewith actuatingmeans arranged to control the firing of said gun.

' 5. An aircraft having a positionally fixed structure portion, a shaft mounted upon said aircraft to extend substantially toward said fixed structure portion and to be'rotatable about its longitudinal axis, a gun mount post carried by said shaft to extend therefrom in a transverse direction and to be rotatable about an axis substantially intersecting the longitudinal axis of rotation of said shaft, a gun mounted upon said gun mount post so as to be pivotable relative thereto about an axis extending in a direction transverse to the direction of the axis of rotation of said gun mount post relative to said shaft, a tracer finger swivelly connected at one end to an end portion of said shaft and extending therefrom toward said fixed structure portion, a templet fixed upon said aircraft and having an inner surface portion of spherical form engaging the free end of said finger in abutting relation and centered upon the position of intersection of said shaft longitudinal axis and said second mentioned axis, link means connecting at one of its ends with said gun at a position spaced from the axes of said pivotal mountings and connecting at the other of its ends with said finger at a position spaced from said swivel connection so as to 6. An aircraft, a gun adjustably mounted thereon, said aircraft having a fixed structure portion facing said gunv under certain conditions of gun adjustment, said gun being mounted uponintersecting said shaft longitudinal axis and about another axis disposed transversely of, said second mentioned axis, atracerfinger swivelly connected at one end to an end portion of saidshaft and extending therefrom toward said fixed structure portion, a temple-t fixed upon said aircraft and having an inner surface portion of spherical form engaging the-free end of said finger in abutting relation and centered upon the position of intersection of said shaft longitudinal axis and said second mentioned axis, link means.

connecting at one of its ends with'saidgun at a position spaced from the axes ofsaid pivotal mountings and connecting at-the other of its ends with said finger at a position, spaced from said swivel connection was to cause said finger tomove relative to-said templet in accord with movements of said gun relative to the direction of said fixed structure portion, ,said-templet being provided with tracer finger contact surface portions contoured to correspond to the outline of said fixed structure portion as viewed from the position of said gun andadapted to register with saidfinger to providc in cooperation therewith actuating means arranged-to control the firing of said gun.

In combination, a support, a gun mount post ccnnectedwto. extendfrom said support while being nivotable relative tov said support about two intersecting axes, a gun mounted upon said post,

to be pivotable relative vthereto about an axis extending in a direction transversely of one of said, pivoting axes of said gun mount post, a gun fire control templetof spherically curved form, fixed to said support so as to be centered sub-v stantially upon the intersection of said axes of pivoting of said gun mount post relative to said support, a gun fire control tracer mounted upon an arm extending, into swivel connection with said support at substantially the position of intersection of said axesoi pivoting of said gun mount post relative to said; support, said tracer being disposed to slidably abut said templet for actuation thereby to control firing operations of said gun, and means operable by aiming movements of said gun to displace saidtracer relative to said templet in direct relation to the aiming'movemerits of said gun.

, 3. In combination, ,a support, a gun mount, post connected to extend from said support while being pivota-ble relative tosaid support about two intersecting axes, a gun mountedupon said, post to, be'pivotable, relative theretonabout an; axis extending in a direction transversely of oneof said pivoting axes of said .gun mount post, agun fire control templet of spherically curved form-fixed to said support so as to be centered substantially upon theintersection of said axes of pivoting of said gunnmou nt post relative to said support, a gun fire controlltracermounted upon an arm extending into swivel connection with said support at substantially the position of intersection of said axes .of pivoting of said gun mount post relative to said support said tracer being disposed-to-slidably abut said templet for actuation thereby to control firing operations of said gun, and means operable by aiming movements of said gun, to swing said tracer so as to displace the abutting end portion thereof relative to said templet in direct relation to the aiming movements of said gun, said gun support including structural portions extending into the range of fire of said gun, and said templet including a silhouette pattern portion corresponding substantially to the silhouette of said extending structural portions as viewedfrom the position of said gun and adapted to cooperate withsaid tracer when in registry therewith to interrupt the fire of said gun. l n v ROBERT, N. .LESNICK, 

